View on GitHub

MessageSerializer

The MessageSerializer uses C# to serialize classes to an array of bytes and vice-versa while automatically calculating fields such as lengths and CRCs.

Blob Fields (Length/Value Pairs)

Often there will be more than one field in a message that is variable length. For those fields, there is usually a length field that is specifically for one particular variable length field. These length/value pairs in the MessageSerializer are referred to as Blob Fields.

They can be defined by using the BlobType property of the MessageProperty attribute as shown:

[MessagedProperty(BlobType = BlobTypes.Length)]
int BlobLength { get; set; }
[MessageProperty(BlobType = BlobTypes.Data)]
string BlobData { get; set; }

Some notes:

Similar to Length properties in a message the MessageSerializer will compute and automatically fill in the Blob Length property.
The Data field does not actually have to be a variable length type and it can also be an IMessageSerializable class or a List of some type (and thus actually contain multiple fields).
There can be any number of Blob Fields in a message.
If a Blob Length field is detected, by default the next encountered Blob Data property is expected to be the Data associated with that Length. If a different property should be used the AssociatedBlobProperty property of the MessageSerializedProperty of the Blob Length property should be set to the name of the property that the data should be associated with.

As an example of the AssociatedBlobProperty in the following example class, MeterSize2 will be associated with BcdValue2 and MeterSize will be associated with BcdValue even though neither Length/Value pair appear next to each other in the message and they occur in a different order in the message.

public class DoubleGapBlob : IMessageSerializable
{
	[MessageSerializedProperty(BlobType = BlobTypes.Length, AssociatedBlobProperty = "BcdValue2")]
	public byte MeterSize2 { get; set; }

	[MessageSerializedProperty(BlobType = BlobTypes.Length)]
	public byte MeterSize { get; set; }

	public int SomeOtherField { get; set; }
	public short OtherField { get; set; }

	[MessageSerializedProperty(BlobType = BlobTypes.Data)]
	public ulong BcdValue { get; set; }

	[MessageSerializedProperty(BlobType = BlobTypes.Data)]
	public int BcdValue2 { get; set; }
}